Data.Text.Format.Heavy

This is the main module of text-format-heavy library.

In most cases, you need to import only this module, and probably also the Data.Text.Format.Heavy.Time module, if you want to format time/date values.

This package exports the format function and Format data type. The Format type implements the instance of IsString, so in the code you may use formatting strings as literals, if you enable OverloadedStrings extension.

Formatting strings syntax is based on Python's string.format() syntax.

The simple usage example is

{-# LANGUAGE OverloadedStrings #-}
module Main where

import Data.Time
import qualified Data.Text.Lazy.IO as TLIO
import Data.Text.Format.Heavy
import Data.Text.Format.Heavy.Time

main :: IO ()
main = do
  name <- getLine
  time <- getZonedTime
  TLIO.putStrLn $ format "Hello, {}! It is {:%H:%M:%S} now." (name, time)

Documentation

module Data.Text.Format.Heavy.Types

module Data.Text.Format.Heavy.Formats

format :: VarContainer vars => Format -> vars -> Text

The main formatting function. This function throws error if some error detected during format string parsing or formatting itself.

type WithDefault c = ThenCheck c DefaultValue

Convenience type synonym.

data ThenCheck c1 c2

Combiled variable container, which uses parameters from c1, and if variable is not found there it will check in c2.

Constructors

ThenCheck c1 c2

Instances

(ClosedVarContainer c1, ClosedVarContainer c2) => ClosedVarContainer (ThenCheck c1 c2)

Defined in Data.Text.Format.Heavy.Instances

Methods

allVarNames :: ThenCheck c1 c2 -> [VarName]

(VarContainer c1, VarContainer c2) => VarContainer (ThenCheck c1 c2)

Defined in Data.Text.Format.Heavy.Instances

Methods

lookupVar :: VarName -> ThenCheck c1 c2 -> Maybe Variable

data DefaultValue

Variable container which contains fixed value for any variable name.

Constructors

DefaultValue Variable

Instances

VarContainer DefaultValue

Defined in Data.Text.Format.Heavy.Instances

Methods

lookupVar :: VarName -> DefaultValue -> Maybe Variable

data Shown a

Values packed in Shown will be formatted using their Show instance.

For example,

formatText "values: {}." (Shown (True, False)) ==> "values: (True, False)."

Constructors

Shown

Fields

• shown :: a

Instances

Eq a => Eq (Shown a)

Defined in Data.Text.Format.Heavy.Instances

Methods

(==) :: Shown a -> Shown a -> Bool

(/=) :: Shown a -> Shown a -> Bool

Show a => Show (Shown a)

Defined in Data.Text.Format.Heavy.Instances

Methods

showsPrec :: Int -> Shown a -> ShowS

show :: Shown a -> String

showList :: [Shown a] -> ShowS

Show a => Formatable (Shown a)

Defined in Data.Text.Format.Heavy.Instances

Methods

formatVar :: VarFormat -> Shown a -> Either String Builder

data Several a

Container for several parameters of the same type. Example usage:

format "{} + {} = {}" $ Several [2, 3, 5]

Constructors

Several

Fields

• getSeveral :: [a]

Instances

Eq a => Eq (Several a)

Defined in Data.Text.Format.Heavy.Instances

Methods

(==) :: Several a -> Several a -> Bool

(/=) :: Several a -> Several a -> Bool

Show a => Show (Several a)

Defined in Data.Text.Format.Heavy.Instances

Methods

showsPrec :: Int -> Several a -> ShowS

show :: Several a -> String

showList :: [Several a] -> ShowS

Formatable a => ClosedVarContainer (Several a)

Defined in Data.Text.Format.Heavy.Instances

Methods

allVarNames :: Several a -> [VarName]

Formatable a => VarContainer (Several a)

Defined in Data.Text.Format.Heavy.Instances

Methods

lookupVar :: VarName -> Several a -> Maybe Variable

data Single a

Container for single parameter. Example usage:

format "Hello, {}!" (Single name)

Constructors

Single

Fields

• getSingle :: a

Instances

Eq a => Eq (Single a)

Defined in Data.Text.Format.Heavy.Instances

Methods

(==) :: Single a -> Single a -> Bool

(/=) :: Single a -> Single a -> Bool

Show a => Show (Single a)

Defined in Data.Text.Format.Heavy.Instances

Methods

showsPrec :: Int -> Single a -> ShowS

show :: Single a -> String

showList :: [Single a] -> ShowS

Formatable a => ClosedVarContainer (Single a)

Defined in Data.Text.Format.Heavy.Instances

Methods

allVarNames :: Single a -> [VarName]

Formatable a => VarContainer (Single a)

Defined in Data.Text.Format.Heavy.Instances

Methods

lookupVar :: VarName -> Single a -> Maybe Variable

Formatable a => Formatable (Single a)

Defined in Data.Text.Format.Heavy.Instances

Methods

formatVar :: VarFormat -> Single a -> Either String Builder

withDefault :: VarContainer c => c -> Variable -> WithDefault c

Use variables from specified container, or use default value if variable is not found in container.

optional :: VarContainer c => c -> WithDefault c

Use variables from specified container, or use empty string variable is not found in container.